Anode locking means



Patented June 16, 1942 UNITED STATES PATENT OFFICE AN-ODE LOCKING MEANSEugene H. Reid, Schenectady, N. Y., assignor to General ElectricCompany, a corporation of New York 6 Claims.

My invention relates to anode structures for mercury arc rectifiers ofthe iron tank type or like devices, particularly to locking means forthe anodes and anode stems or studs of such rectifiers, and it object isto effect improvements in locking means for structures of thischaracter.

In anode structures for mercury arc rectifiers of the iron tank type theanode proper or anode tip is commonly insulatingly mounted on the tankby means of an anode stem or stud to the lower end of which the anodetip is screwed. The anode seal, connected to the tank cover or wall,includes an insulating member having a hole formed therethrough for thepassage of the anode stem, and a metal insert moulded into theinsulating member. A terminal member of suitable material is welded tothe insert, the hole in the insert for the passage of the anode stem iscontinued through the insert and into the terminal member, and the anodestem is screwed into the terminal member.

In the use of anode structures as above described difiiculties have beenencountered due to the tendency of the anode tip to shake loose duringshipment or operation and to unscrew from the anode stem, and also tothe tendency of the anode stem under like conditions to shake loose inthe terminal member.

In copending application, Serial No. 419,918, of Carl C. Herskind, filedNovember 21, 1941, and assigned to the same assignee as the presentapplication, for overcoming the above-described difficulty in the use ofthe above-described and like anode structures a disengageable means forlocking the anode stem to the metal member which projects within theseal insulating member is disclosed, and further, dlsengageable meansfor locking the anode tip against rotation with reference to the anodestem. For this purpose, in the above mentioned copending application, asleeve surrounding the anode stem is provided, the sleeve beingdisengageably locked at its lower end to the anode stem and tip. Thesleeve extends upwardly, however, only to a point within the metalinsert which is moulded within the seal insulation. Cooperating disen--gageable locking, means are provided at this point which include ashoulder and a keyway formed in the inner wall of the metal insertand acorresponding key'formed in the end of the sleeve.

It has been found that in the manufacture of the locking means thusprovided in the sleeve and metal insert as above described, considerabledifficulties are encountered caused, among other reasons, by therelative inaccessibility .of the inner wall of the metal insert in whichthe keyway is formed, the operation of machining the insert to providethe keyway being preferably performed after the insert is moulded intothe insulation and the seal is in otherwise finished condition.

The present invention is an improvement on the anode structure lockingmeans of the above entitled application. In accordance with the presentinvention the last-mentioned difliculty and other difficulties areovercome by extending the locking sleeve of the above-entitled priorapplication upwardly entirely through the metal insert and intoengagement with the terminal member which is present above the metalinsert and is fastened thereto, in the process of manufacture, bywelding.

The novel features which are characteristic of my invention are setforth with particularity in the appended claims. The invention itself,however, both as to its organization and method of operation togetherwith further objects and advantages thereof may best be understood byreference to the following description taken in connection with theaccompanying drawing in which Fig. 1 is a sectional view of an anodestructure in which my invention has been embodied, and Figs. 2 and 3 aredetail views illustrating a disen'gageable locking means.

Referring to Fig. 1, the numeral l designates an anode tip preferably ofgraphite having a flat upper surface 2 and a threaded central opening 3,and the numeral 4 designates an anode stem or stud having a threadedportion 5 to which the anode tip I is adapted to be screwed. The numeral6 designates an anode seal which includes an insulating member 1. Ametal member 8 which is mounted upon the insulating member I andprojects upwardly therefrom is constituted by a metal insert 9 which ismoulded into and projects a considerable distance within the insulatingmaterial and also projects above the upper surface thereof, and by ametal terminal member III which is welded to the upper extremity of theinsert 9. A hole II is bored through the lower portion of insulatingmember I and this hole continues on through the insert 9, no shoulder orkeyway being required in the insert. A hole is bored also partly throughthe terminal In, the latter member being threaded to receive thethreaded upper portion l2 of the anode stem 4.

To look disengageably the anode stem 4 against rotation with respect tothe metal member 8, a

metal member or sleeve I3 is provided surrounding a portion of the anodestem 4 and projecting upwardly from the anode tip I. The sleeve I3projects upwardly through the lower part of the insulating member I asin the locking means disclosed in the above-mentioned copendingapplication Serial No. 419,918. However, instead of the sleevecontinuing only to a shoulder formed at a point in the lower portion ofinsert 9, as provided in the above-mentioned application, in accordancewith my present invention the sleeve I3 projects through the insert 9and abuts against the lower extremity of the termmal III.

The sleeve I3 is adapted to be locked to the terminal II] by providingon the inner extremity of the terminal, as better shown in Fig. 2, adownwardly depending annular or like portion l4 fitting within the upperextremity of the insert 9, and by cutting a keyway, as I5, in thisannular portion, a corresponding key I6 adapted to fit into thekeywaybeing formed on the upper extremity of the sleeve I3, as better shown inFig.3.

Since the terminal I is a piece of the metal member 8 which is initiallyentirely separate from the other piece, insert 9, of member 8, thereforethe annular portion I4 and keyway I are easily formed on the end ofterminal I0 before assembly, the finished terminal piece then beingwelded to the insert piece and thus bringing the locking means, keywayI5, associated with the terminal i0 into proper position within hole IIto receive the cooperating locking means, key I5, of sleeve I3.

To look disengageablyv the anode tip I to the sleeve member I3 anysuitable means may be employed, such, for example, as disclosed in thebefore-mentioned copending application, Serial No. 419,918, wherein thesleeve is pinned if desired at its lower extremity to the anode stem andrelative rotation of the anode tip and the sleeve is prevented by screwstraversing an extension or flange portion of the sleeve and threadedinto the anode tip. Preferably, however, the anode tip is locked againstrotation relative to the sleeve by means similar to those disclosed incopending application SerialNo. 396,584, filed June 4, 1941, wherein thelocking means includes, essentially as shown in Fig. 1 of the presentapplication, a

flat washer I1 mounted between the anode tip I and a sleeve extensionorflange portion I8 in a recess I9 formed therein. Tabs or ears, as 20,on the washer I! extend upwardly into corresponding holes, as 2 I, inthe flange I8, and other tabs or ears, as 22, extend downwardly intocorresponding holes, as 23, in the anode tip I.

In assembling the illustrated anode structure incorporating the lockingmeans in accordance with my present invention, the metal member orsleeve I3 is first slid on to the anode stem 4 which, to prevent bindingof the sleeve I3 thereon and to permit greaterease of assembly, ispreferably provided with short shoulderportions 24, 24, betweenwhich'is'a relieved section 25 or section of reduced diameter.

The anode stem 4 is then inserted into the seal 6. The sleeve I3 is nextpushed through the lower, portion of the insulating member 'I and onthrough the insert 9 up to the lower extremity of the terminal memberII] and rotated until the key or tab I6 fits into the slot or keyway I5formed in the annular downwardly projecting portion I4 of terminalmember .IIl;,The anode ID, the parts being so proportioned that when thestem 4 is in its desired position in the terminal III the upperextremity of the sleeve I3 abuts against the lower extremity of theterminal I0 while the lower extremity of the sleeve I3 abuts against ashoulder 26 formed on the stem 4 at the beginning of the threadedportion thereof.

The hole II, as shown in Fig. 1 of the present application, is astraight hole which is drilled through the lower portion of theinsulating member I and then entirely through the insert 9, in-

' stead of a hole requiring a shoulder in the instem .4 is thenscrewedinto theterminal member terior of the insert as in the system disclosedin the above-mentioned application, Serial No. 419,918. Therefore, aclose fit is easily made possible between the sleeve I3 and the insert9, thereby materially facilitating the accurate alignment of the sleeveI3 and the anode stem 4.

When the anode stem 4 is threaded into its desired position in terminalmember ID, as above described, the sleeve I3 is held in final positionlongitudinally so that it is firmly locked to the terminal member ID andcannot be rotated with respect thereto.

The washer I1 is next placed on the face 2 of the anode tip I with earsor tabs, as 22, of the washer bent down into the corresponding holes 23of the tip. The anode tip I is then screwed to the threaded portion 5 ofthe anode stem 4 until the stem flange portion I8 and the surface 2 ofthe tip are in close contact, with holes, as 2|, of the stem flangeportion in alignment with corresponding holes, as 21, in the anode tip.Other ears or tabs, as 20, are then bent up into their correspondingholes, as 2|, in the stem flange portion I8 by means of a rod (notshown) inserted through the holes 21 provided for that purpose in thetip I.

, The anode tip I is thus locked against rotation with respect to thesleeve I3, and as the sleeve I3 is locked by the key I6 and keyway I5against rotation with respect to terminal III, therefore theanode tip Iis also locked against rotation with respect to the terminal member.

The anode structure thus assembled may be readily disassembled by firstbending up the ears or tabs 22 of washer I 1 to free the anode tip,'andthereafter reversing the above described steps of theassembly process.

My invention hasbeen described herein in a particular embodiment forpurposes of illustration. It is to be understood, however, that theinvention is susceptible of various changes and modifications and thatby the appended claims I intend to cover any such modifications as fallwithin the true spirit and scope of my invention.

What I claim as new and desire to-secure by Letters Patent of the UnitedStates is:

1. In combination, an insulating member for an anode seal, a metalinsert projecting within said insulating member, a terminal memberfastened to the outer extremity of said insert, an anode stem traversingsaid insulating member and said insert and screwed to said terminalmember, an anode tip screwed to said stem, and means to prevent rotationof said anode tip with respect to said terminal member, saidmeansineluding a member extending from said tip to the inner extremityof said terminal member to lock disengageably said last-named member tosaid terminal member and to said anode tip.

2. In combination, an insulating memberfor an anode seal, 1 a -metalinsert projecting within said insulating member,.a terminal memberfastened to the outerextremity ofsaid insert, an

anode stem traversing said insulating member and said insert and screwedto said terminal member, an anode tip screwed to said stem, and means toprevent rotation of said anode tip with respect to said terminal member,said means including a sleeve enclosing the portion of said anode stembetween said tip and said terminal member, said sleeve beingdisengageably connected at its outer extremity to said terminal member,and means to prevent relative rotation of said tip and said sleeve.

3. In combination, an insulating member for an anode seal, a metalinsert projecting within said insulating member, a terminal memberconnected to the outer extremity of said insert, an anode stem screwedto said terminal member, an anode tip screwed to said stem, and means toprevent rotation of said anode tip with respect to said terminal member,said means includin a sleeve enclosing a portion of said stem, saidsleeve being disengageably connected at its outer extremity to the innerextremity of said terminal member and having an extension at its otherextremity abutting against said anode tip, and means associated withsaid tip and said extension of said sleeve to prevent relative rotationof said tip and said sleeve.

4. In combination, an anode terminal member, an anode seal including aninsulating member and a metal insert therein fastened to said terminalmember, an anode stem projecting through said insulating member and saidinsert and screwed to said terminal member, an anode tip screwed to saidstem, a metal sleeve on said stem having a flange portion and extendingfrom said tip to said terminal member, means associated with saidterminal member and the outer extremity of said sleeve to lock saidterminal member to said sleeve to prevent relative rotation thereof anddisengageable when said stem is unscrewed from said terminal member, andmeans associated with said anode tip and said sleeve flange portion tolock said tip to said flange portion to prevent relative rotationthereof.

5. In combination, an anode stem, a sleeve surrounding a portion of saidstem, an anode seal including an insulating member having an inserttherein projecting therefrom, said insert and a portion of saidinsulating member having a hole of uniform diameter therethrough toreceive said sleeve, a terminal member having a threaded hole adapted tohave said stem screwed therein, said terminal member being adapted to beattached at its inner extremity to the outer extremity of said insert,cooperating means to lock detachably said sleeve against rotation withrespect to said terminal member, said means including a member formed onsaid terminal member at the inner extremity thereof before saidattachment thereof to said insert and adapted to engage a correspondingmember formed on said outer extremity of said sleeve, an anode tipscrewed to the inner extremity of said stem, and means to preventrotation of said tip with respect to said sleeve.

6. In combination, an anode stem, a sleeve surrounding a portion of saidstem, an anode seal including an insulating member having an inserttherein projecting therefrom, said insert and a portion of saidinsulating member having a hole of uniform diameter therethrough toreceive said sleeve, a terminal member having a threaded hole adapted tohave said stem screwed therein, said terminal member being adapted to beattached at its inner extremity to the outer extremity of said insert,means to lock detachably said sleeve against rotation with respect tosaid terminal member including a portion of said sleeve projecting fromthe outer extremity thereof and engaging a corresponding portion of saidterminal member projecting from the inner extremity thereof into saidhole of said insert, said last-named portion being adapted to be formedon said terminal member before said attachment thereof to said insert,an anode tip screwed to the inner extremity of said stem, and means toprevent rotation of said tip with respect to said sleeve.

EUGENE H. REID.

